The Process of Scientific Inquiry
Westerly Middle School Science2010-2011
• Cover one eye, then stare at the center of the flag for one minute. Keeping your eye focused on the screen…
What do you see?
Retinal fatigue
• Example: camera flash– Flash is so intense it fatigues photoreceptive cells in your
retina so they are temporarily unresponsive to light• Flag: – See the complementary color of the object
• Stare at red dot, you will see cyan afterimage– Light reflected from white is all wavelengths (colors)
stimulates red, green, and blue cones (photoreceptive cells)
– If fatigue red cones, only the green and blue are stimulated (cyan)
– Black stars, yellow field, black and cyan (blue) stripes• Should see red, white, and blue!
The importance of observation…
• Michael Faraday (1791-1867) – British scientist– First electric motor, magnetism and light, electricity and
chemical bonding• Be careful when observing – not to rely solely on prior
knowledge to explain what you see
• Observations of a Candle…– In your science lab notebook (SciNB), write down all
observations of the candle experiment…
Observing a Candle
• Types of observations– Flame– Condensate– Deposits– Smoke– Candle (Paraffin)– Wick– Odors– Sound– Heat
Developing Questions About the Candle
• Michael Faraday: “…I hope you will always remember that whenever results happen, especially if it be new, you should say, ‘What is the cause? Why does it occur?’ and you in the course of time will find out the answer.”
• In SciNB:– Write down as many questions as you can based on
the observations you made– Ex: “what is wax? What is the wick? Why does the
indicator turn color when placed over the candle?
Writing Research Questions
• Observational questions, “what is my gas mileage?”– Others examples?
• Cause-and-effect questions, “Will my car get better gas mileage at 60 or 65 miles per hour?”– Other examples?
Writing Observational Research Questions
• Most research starts with ___________.• Observations!• What do we look for? • (think about the cubes)• Patterns and trends
• Working with Questions worksheets
Writing Observational Research Questions
• Observations studies can be quantitative or qualitative but are not experimental– Researcher records measurements and
descriptions but does not alter independent* variables* to see their effect
– *more on these soon
SciNB: Review list to identify quantitative (require the recording of specific numbers) and which are qualitative
(based on quality or character)1. Are AM or FM radio signals stronger in tunnels?2. Do soap bubbles last longer on warm or cold days?3. What percentage of my class is right-eye-dominant?4. Is the density of aphids greater on the top or bottom of rose
leaves?5. What is the current pH of my home tap water?6. What is the average height of 2-week-old radish seedlings?7. What is the maximum acceleration of the world’s fastest roller
coaster?8. Are earthquakes more common near the coasts or inland?9. Which cloud types are associated with rainstorms?10. What is the average base height of cumulus clouds?
11. Write two quantitative and two qualitative observational questions.
QualQualQuanQual
QuanQuanQuan
QualQualQuan
Writing Experimental Research Questions
• Compare experimental sample vs control sample• Must include independent and dependent variables
and a subject:– The independent variable is the variable that the
researcher selects or changes to determine if it produces changes in the dependent variable
– **A researcher looks for evidence that changes in the independent variable are correlated with changes in the dependent variable
• Must also include conditions – the parameters (structure/limits) under which the study is conducted and may include any of a variety of key factors such as temperature, light intensity, and pH…
Independent VariableIndependent Variable
Dependent VariableDependent Variable
Writing Experimental Research Questions - Formula
• “What is the effect of (independent variable) on (dependent variable) in (subject) at (conditions)?”
• “What is the relationship of (independent variable) to (dependent variable) in (subject) at (conditions)?”
Independent Variable What you decide to vary in your experiment
Dependent Variable What changes as a result of the independent variable changing
Conditions (Control Variables) What stays the same for all trials – environmental/location/time/ etc.
Subject The subject you are looking at / observing
Plant HeightTemperaturePlant TypeBean PlantSunlightFertilizer
Plant HeightTemperaturePlant TypeBean PlantSunlightFertilizer
Mazda MiataWeather 405 NorthTire treadTime to go 0 to 60 mph
Mazda MiataWeather 405 NorthTire treadTime to go 0 to 60 mph
Identify…• Identify the independent variable, dependent variable,
subject, and conditions in each of the sample life science questions:– (a) What is the effect of running at different speeds on the
heart rate of healthy 17-year old boys at National High School
– (b) How does the photosynthetic rate of pondweed (Elodea canadensis) vary with light intensity at 30oC?
– (c) At what temperature does baker’s yeast (Saccharomyces cerevisiae) respire the most when placed in 0.1 molar sucrose solution?
– (d) At which concentration of polyacrylamide gel do blood proteins separate the best when performing gel electrophoresis?
– (e) Which antibiotic is most effective in killing Staphylococcus growth in agar plates kept at 37oC
LS
• Identify the independent variable, dependent variable, subject, and conditions in each of the sample life science questions:– (a) What is the effect of running at different speeds on the heart rate
of healthy 17-year old boys at National High School– (b) How does the photosynthetic rate of pondweed (Elodea
canadensis) vary with light intensity at 30oC?– (c) At what temperature does baker’s yeast (Saccharomyces
cerevisiae) respire the most when placed in 0.1 molar sucrose solution?
– (d) At which concentration of polyacrylamide gel do blood proteins separate the best when performing gel electrophoresis?
– (e) Which antibiotic is most effective in killing Staphylococcus growth in agar plates kept at 37oC
Independent Variable Dependent Variable Subject Conditions
(a) Running Heart rate 17-yr-old boys National HS
(b) Light intensity photosynthesis pondweed 30oC
(c) temperature respiration Baker’s yeast 0.1 M sucrose
(d) concentration separation Blood proteins electrophoresis
(e) antibiotic Death of bacteria Staphylococcus Agar at 37oC
Identify• Identify the independent variable, dependent variable,
subject, and conditions in each of the sample life science questions:– (a) How is the diffusion rate of air freshener affected by
temperature at standard atmospheric pressure?– (b) What effect does temperature have on the rate of
sugar (sucrose) crystal formation in saturated sugar solutions?
– (c) What is the relationship of the number of turns of 20-gauge copper wire to magnetic field strength in a simple electromagnet?
– Which metal serves as the best electrode for producing hydrogen in an electrolysis device at standard temperature and pressure?
– (e) What effect does the volume of nitrogen gas have on temperature if pressure is kept constant?
PS
Independent Variable Dependent Variable Subject Conditions
(a) temperature Diffusion rate Air freshener 1 atm
(b) temperature Rate of crystallization
sucrose Saturated solutions
(c) turns Magnetic field 20 gauge Cu wire electromagnet
(d) metal H production Electrode 1 atm, 0oC
(e) volume temperature nitrogen gas Constant P
• Identify the independent variable, dependent variable, subject, and conditions in each of the sample life science questions:– (a) How is the diffusion rate of air freshener affected by temperature at
standard atmospheric pressure?– (b) What effect does temperature have on the rate of sugar (sucrose)
crystal formation in saturated sugar solutions?– (c) What is the relationship of the number of turns of 20-gauge copper
wire to magnetic field strength in a simple electromagnet?– Which metal serves as the best electrode for producing hydrogen in an
electrolysis device at standard temperature and pressure?– (e) What effect does the volume of nitrogen gas have on temperature if
pressure is kept constant?
Brainstorming and Hypothesizing
• What is “Brainstorming”?• Why brainstorm?• Generate possible solutions to difficult
problems, particularly in the hypothesis generation phase of the scientific method
Lost on the Moon
Apollo Lunar Module (LM) was the lander portion of the Apollo spacecraft
Apollo Lunar Module (LM) was the lander portion of the Apollo spacecraft
Lost on the MoonYou are members of a scientific team bound for a permanent
research station on the surface of the Moon. Unfortunately, your lunar craft malfunctions, forcing an emergency landing in Mare Crisium, approximately 300 km from the research station at Mare Serenitatis. Both you and the research station are currently on the lighted surface of the Moon.
During the landing process, much of the equipment aboard has been damaged, and since survival depends on reaching the research station, only the most critical items must be chosen for the trek.
On the next slide you will find a list of the 15 items left intact following the emergency landing. As a group, you must reach consensus regarding the relative importance of these items in your mission to reach help at the research station.
Lost on the Moon Compare/Contrast: EARTH MOON
Mass (1024kg) 5.97 0.073Diameter (km) 12,756 3475
Density (kg/m3) 5515 3340Gravity (m/s2) 9.8 1.6
Escape Velocity (km/s) 11.2 2.4
Rotation Period (hours) 23.9 655.7
Length of Day (hours) 24 708.7
Distance from Sun (106 km) 149.6 0.384*
Perihelion (106 km) 147.1 0.363*
Aphelion (106 km) 152.1 0.406*
Orbital Period (days) 365.2 27.3
Orbital Velocity (km/s) 29.8 1
Orbital Inclination (degrees) 0 5.1
Orbital Eccentricity 0.017 0.055
Axial Tilt (degrees) 23.5 6.7
Mean Temperature (C) 15 -20
Surface Pressure (bars) 1 0
Number of Moons 1 0Ring System? No No
Global Magnetic Field? Yes No
15 items:
Box of matches
Two 100 kg tanks of oxygen
Stellar map (stars)
10 kg dehydrated food
Traditional signal flares
First aid kit
50 m of nylon rope
Solar-powered FM radio
10 L water
Portable heating unit
Two 45 caliber pistols
Case of dehydrated milk
Life raft Magnetic compass
Parachute silk
Lost on the Moon1. Brainstorming: Write down as many ideas as possible regarding the
potential use of the following 15 items in your trek to the research station. Do not discuss or evaluate the merit of the ideas expressed.
2. Analysis: Review the maps, photos, movies and data on the moon available on the website (http://www.csun.edu/science/geoscience/astronomy/moon/index.html ), recording the similarities and differences between the earth and the moon with respect to gravity, atmosphere, lighting, radiation, magnetic field, visibility, surface, etc.
3. Evaluation and consensus building: Discuss the merits of the ideas presented during the brainstorming session, and develop a consensus within your group regarding the relative value of each item. Place a 1 by the item you value most and a 15 by the item you value least, recording the rational for your ranking
4. Discussion and defense of position: Compare your ranking with those of other groups. If there are differences, discuss them, presenting reasoned arguments for your ranking.
Developing a Plan:Writing Unambiguous Procedures
• SciNB: write directions for one of the following. Your directions should be unambiguous so that they can be followed without any assumptions – Stuffing an envelope– making a sandwich– applying a Band-Aid to a small cut on a finger– putting on a jacket– how to reach the Main Office from the science room
Developing a Plan
• Stage 1: The General Plan– Identify the variables in the system being studied and
determine• what will be changed (the independent variable)• what will stay the same (the control variables), and • the outcome to observe or measure (the dependent variable)
– “fair test – when only one thing (variable) is changed for the investigation.”
• Stage 2: The Operational Plan– The sequence of procedures, events, or steps that will be
taken by the student during the investigation.– Can include the materials used for the investigation
Developing a Plan
• The General Plan:– List the variables you are examining:________________ _______________________________ _______________
Developing a Plan
• Data Organization:– ask yourself:• How will you collect your data?• What will you use to collect and record your data?• What will your data collection device look like?
Friday’s Quiz
• Skills to Practice:1. Making observations (such as a candle)2. Clearly describing what you may do, given a list
of items (similar to candle, funnel bromothymol blue, etc.)
3. Writing investigatable questions4. Proposing how you will investigate the question
and the evidence you need to collect5. Identifying variables6. Writing clear procedures
